Nota Lepidopterologica
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©Societas Europaea Lepidopterologica; download unter http://www.biodiversitylibrary.org/ und www.zobodat.at Nota lepid. 8 (4) : 351-362 ; 31.XII.1985 ISSN 0342-7536 On a Gracillaria species from Morocco with some supplementary notes on the genus Gracillaria Haworth (Lepidoptera : Gracillariidae) W. O. De Prins Diksmuidelaan 176, B-2600 Antwerpen (Belgium) Abstract A new Gracillariid species is described from Morocco : Gracillaria toubkalella n. sp. The lectotype of Coriscium norvegiellum Wocke, 1893 is designated and the synonymy of this taxon with Gracillaria loriolella Frey, 1881 is established. Résumé L'auteur décrit une nouvelle espèce de Gracillariidae provenant du Maroc : Gracilla- ria toubkalella n. sp. Il désigne le lectotype de Coriscium norvegiellum Wocke, 1893 et établit la synonymie de cette espèce avec Gracillaria loriolella Frey, 1881. Introduction In April 1983 I was able to breed some specimens of a Gracillariid species of which I found full grown larvae in twisted Fraxinus leaves in the garden of the Grand Hotel du Toubkal at Asni (Morocco, High Atlas). Almost immediately after their capture the larvae began to construct a pure white silken cocoon between the leaves, against the lid of the box in which they were contained or in the edges ofthat box. The first imago emerged on 20th April 1983. A total of 19 males and 20 females emerged between that date and 29th April. The specimens remained undetermined for about two years, in spite of thoroughly searching the series of Gracillariidae in the museums of Amsterdam, Brussels, Leyden and London and a heavy correspondance with several European specialists on the matter. It became clear that the Moroccan species was new to science and I would like to describe it in this paper as Gracillaria toubkalella n. sp. Male : head ochreous, mixed with brown scales, front brown with scattered ochreous scales. Labial palpi upturned, mixed ochreous and brown, with 351 ©Societas Europaea Lepidopterologica; download unter http://www.biodiversitylibrary.org/ und www.zobodat.at distinctive ochreous tips. Maxillary palpi short, upturned or porrected, same colour as labial palpi. Antennae dark brown, each segment somewhat lighter towards base. Tegulae and thorax ochreous, with scattered brown scales in front. Forewing groundcolour dark brown, almost black, each scale with grey base and dark brown tip. A very small ochreous spot near base and some scattered ochreous scales near base of inner margin. An oblique white fascia at about 1/3, gradually getting obscure towards costa, and preceeded by a small area of ochreous scales above the wings half. Another white fascia towards middle of wing, curved outwards and connected on the inner margin with the first fascia forming the letter U. The second fascia only reaching to middle of wing. Some black tipped scales at inner margin on the white U, forming some small but very contrasting dots. Space in white U filled with ochreous scales to make a uniform ochreous area which extends above second white fascia along costa to well beyond half the wings length. Two smaller ochreous dots on costa towards apex. Some scattered ochreous scales between white U and outher margin. Apical cilia dark brown forming three longitudinal dark lines. Cilia along dorsum grey. Hindwing grey without markings, cilia grey. Fore and mid legs dark brown, with some whitish scales, tibia white with each segment brown tipped. Hindlegs lighter brown with scattered brown and greyish scales, tips of tibia somewhat darker, (see fig. 1) Male genitalia : tegumen with parallel sides, rounded apically. Tuba analis and subscaphium protruded beyond tegumen. Valva widened apically, ventral margin straight, ventro-apical corner round, outer margin slightly concave, dorso-apical corner rather acute. A distinct heavy chitinised hook at base of costa. Ventro-apical and terminal margins with numerous long setae pointed towards base and costa. Saccus somewhat shorter than valva with two heavy sclerotised ridges towards middle. Aedoeagus straight, shorter than valva, pointed apically and somewhat widened basally. Vesica without cornuti. (see fig. 5) Female : as male, there is no sexual dimorphism. Female genitalia : Papillae anales rather short, setose ; apophyses posteriores very slender, apophyses anteriores of same shape and length as apophyses posteriores. Lamella postvaginalis very weekly sclerotised. Ductus bursae membraneous, very long and slender ; corpus bursae membraneous, almost round, a large sickle-shaped signum, pointing towards middle of bursa and widened at its base, (see fig. 7) Holotype: male, Morocco, High Atlas, Asni, 1150 m, e.l. Fraxinus sp. 26-1V-1983, leg. W. O. De Prins, in coll. British Museum (Natural History). Allotype: female, same data, e.l. 28-1V-1983, in coll. British Museum (Natural History). 352 ©Societas Europaea Lepidopterologica; download unter http://www.biodiversitylibrary.org/ und www.zobodat.at Figure 1 : Gracillaria toubkalella n. sp. : top, Holotype â, Morocco, High Atlas, Asni, 1 150 m, e.l. Fraxinus sp., 26-IV-1983, leg. W. O. De Prins ; bottom, Allotype 9, same data, e.l. 28-IV-1983, both in coll. British Museum (Nat. Hist.). 353 ©Societas Europaea Lepidopterologica; download unter http://www.biodiversitylibrary.org/ und www.zobodat.at Figure 2 : Gracillaria ussuriella (Ermolaev, 1977) ; top 6, Japan, Hokkaido, Fujinosawa, e.l. Fraxinus mandshurica 3-VI-1967, leg. S. Umezawa, det. T. Kumata, 1979 ; bottom 9, Japan, Hokkaido, Sapporo, e.l. Fraxinus mandshurica 24-DC-1966, leg. & det. T. Kumata. 354 ©Societas Europaea Lepidopterologica; download unter http://www.biodiversitylibrary.org/ und www.zobodat.at Paratypes: 18 males and 19 females, same data, e.l. between 20 and 29-IV-1983, in my collection. Paratypes have been placed in the collections of the museums of Amsterdam, Leyden, London and Vienna. il The name toubkalella refers to the highest peak of the Moroccan moun- tains, Jebel Toubkal (4167 m). When I revisited the same spot in July 1984, I noticed that the Fraxinus tree in the hotel garden on which I found the larvae had been cut down. However, I spotted other trees of the same species in the whole area, especially in the private gardens in the small villages along the main road to Oukaimeden. Since I only found larvae of the latest instars, I have no information on the mines of the first instars. The mines which I found were occupied by one larva each, except for some cases where two larvae inhabited the same mine. This could always be seen from the outside, because the leaf was then rolled completely, cigarette-formed. The mines usually occupied one side of the leaf, the larva having rolled it longitudinally and spun it to the mid vein. Occasionally, the top of the leaf was rolled towards the base, but this happened mostly with small leaves. Most larvae left their mine for pupation, though I found some cocoons in the mines. The cocoons are spindle-shaped, silvery white. Gracillaria toubkalella n. sp. is very closely related to G. ussuriella Ermo- laev, specimens of which I have studied from Japan (Hokkaido). Both species are of the same size and the overall pattern of the forewings is very much alike. However, ussuriella shows much more contrast in its colouring due to the almost black scales, contrasting with the pure white and golden-brown scales. The white U is more complete in ussuriella, the distal fascia being only interrupted in the middle by some darker scales. The basal fascia of the white U is much broader than in toubkalella n. sp. In ussuriella the space in the white U is filled with golden-brown scales and there are some pure white strigulae along both wing margins, whereas in toubkalella n. sp. there are no white markings except for the white U. Gracillaria toubkalella n. sp. can be readily distinguished from its two European relatives by its wing pattern and colour. G. syringella Fabricius has white strigulae both on costal and dorsal wing margins. G. loriolella Frey has not the ochreous colouring and shows also white strigulae on both wing margins. The most conspicuous difference in the genitalia lies in the female genitalia : the Signum of Gracillaria toubkalella n. sp. is widened at its base without forming the two characteristic lobes which are present in syringella and loriolella. The genitalia of the species in Gracillaria are very much alike and Kumata "failed to separate them (i.e. the four Japanese species) clearly by these 355 ©Societas Europaea Lepidopterologica; download unter http://www.biodiversitylibrary.org/ und www.zobodat.at Figure 3 : Gracillaria loriolella Frey, 1881 ; top 6, Austria inf. Z., Klosterneuburg, Kuhau, 31 -VIII- 1932, leg. I. Preissecker, det. E. Jäckh, 1972 ; bottom 9, Austria inf., Klosterneu- burg, Kuhau, 27-IX-1933, leg. I. Preissecker, both in coli. Naturhistorische Museum Wien. 356 ©Societas Europaea Lepidopterologica; download unter http://www.biodiversitylibrary.org/ und www.zobodat.at organs." (Kumata 1982 : 8). However, G toubkalella n. sp. can be distin- guished from its relatives by the following characters : valva with concave outer margin, thus making the apex look more pointed than in the other species. Corpus bursae round, Signum broader on its base but without the usual pair of elongated lobes. Additional notes on the genus Gracillaria Haworth, 1828 Vari treated Gracillaria Haworth, 1828 as a subgenus under the genus Caloptilia Hübner, 1825. However, representatives of both groups show important and constant differences in the larval chaetotaxy, the pregenital segments of the male, the female genitalia and the wing venation, as stated by T. Kumata (1982). I follow this author in considering Gracillaria as a valid genus. As far as is yet known only three west palearctic species belong to Gracillaria, i.e. G. syringella (Fabricius, 1794), G. loriolella Frey, 1881 and G. toubkalella n. sp., whereas most of the European species originally described in Gracillaria (mostly spelled as Gracilarid) actually belong to Caloptilia.